Volume 8, Issue 3 (8-2014)                   IJPBS 2014, 8(3): 1-10 | Back to browse issues page

XML Print

Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Mostafavi Abdolmaleky H. Horizons of Psychiatric Genetics and Epigenetics: Where Are We and Where Are We Heading?. IJPBS. 2014; 8 (3) :1-10
URL: http://ijpbs.mazums.ac.ir/article-1-459-en.html
Assistant Professor Department of Psychiatry, Iran University of Medical Sciences, Tehran, Iran AND Research Associate, Department of Genetics and Genomics, Boston University School of Medicine, Boston, MA, USA
Abstract:   (1671 Views)
Today multinational studies using genome-wide association scan (GWAS) for >1000,000 polymorphisms on >100,000 cases with major psychiatric diseases versus controls, combined with next-generation sequencing have found ~100 genetic polymorphisms associated with schizophrenia (SCZ), bipolar disorder (BD), autism, attention deficit and hyperactivity disorder (ADHD), etc. However, the effect size of each genetic mutation has been generally low (<1%), and altogether could portray a tiny fraction of these mental diseases. Furthermore, none of these polymorphisms was specific to disease phenotypes indicating that they are simply genetic risk factors rather than causal mutations. The lack of identification of the major gene(s) in huge genetic studies increased the tendency for reexamining the roles of environmental factors in psychiatric and other complex diseases. However, this time at cellular/molecular levels mediated by epigenetic mechanisms that are heritable, but reversible while interacting with the environment. Now, gene-specific or whole-genome epigenetic analyses have introduced hundreds of aberrant epigenetic marks in the blood or brain of individuals with psychiatric diseases that include aberrations in DNA methylation, histone modifications and microRNA expression. Interestingly, most of the current psychiatric drugs such as valproate, lithium, antidepressants, antipsychotics and even electroconvulsive therapy (ECT) modulate epigenetic codes. The existing data indicate that, the impacts of environment/nurture, including the uterine milieu and early-life events might be more significant than genetic/nature in most psychiatric diseases. The lack of significant results in large-scale genetic studies led to revise the bolded roles of genetics and now we are at the turning point of genomics for reconsidering environmental factors that through epigenetic mechanisms may impact the brain development/functions causing disease phenotypes.
Keywords: -
Full-Text [PDF 86 kb]   (1037 Downloads)    
Type of Study: Research | Subject: Psychiatry
Received: 2014/10/11 | Accepted: 2014/10/11 | Published: 2014/10/11

Add your comments about this article : Your username or Email:
Write the security code in the box

Send email to the article author

© 2018 All Rights Reserved | Iranian Journal of Psychiatry and Behavioral Sciences

Designed & Developed by : Yektaweb